Researchers first discovered a massive brine pool under the Gulf on Mexico in 2014 using a robosub.

Now, they have returned to create the first high resolution map of the area - and say it could hold the key to finding life on other planets.

Scroll down for video

The first high resolution map of the 'jacuzzi of despair' that kills almost anything that swims into it. The circular pool - about 100 feet in circumference and about 12 feet deep - lies nearly 3,300 feet below the surface of the Gulf. This image was created from 2,000 stills taken by a robosub.

WHAT IS IT?

The circular pool - about 100 feet in circumference and about 12 feet deep -- lies nearly 3,300 feet below the surface of the Gulf.

It contains water that is four or five times saltier than the surrounding seawater.

As a result, the brine is so dense that it sits on the bottom, forming an underwater cauldron of toxic chemicals that include methane gas and hydrogen sulfide that doesn't mix with surrounding seawater.

'On the last leg of these seafloor hydrocarbon community investigations, we focused on a larger brine pool dubbed the 'Jacuzzi of Despair,' in reference to its warm temperature (19°C) and high salt content—which can be fatal to many macrofauna unlucky enough to fall in (we observed large dead isopods and crabs that had been preserved along the edge of the brine pool),' the researchers wrote in Oceanography.

'This crater-like, circular, brine-filled pool rose 3 m above the surrounding seafloor, and brine was spilling out on one side in a spectacular 'waterfall.'

'It was one of the most amazing things in the deep sea,' Erik Cordes, associate professor of biology at Temple University who discovered the site along with several colleagues, and published a report on the findings in the journal Oceanography, told Discovery News after a previous visit to the area.

'You go down into the bottom of the ocean and you are looking at a lake or a river flowing.

Share this article

Cordes - who studies deep-sea corals - and others first found the formations in 2014 using a remotely-operated underwater robot called Hercules.

They returned the following year with the three-person research sub Alvin to get a closer look.

Now, their latest study has been published.

The team retrieved some samples of microbial life that are adapted to handle the high salinity and low oxygen levels of the brine pool.

Cordes believes that these creatures could resemble life on planets in our solar system, or beyond.

The team retrieved some samples of microbial life that are adapted to handle the high salinity and low oxygen levels of the brine pool.

A brine pool in the 'jacuzzi of despair', with walls made up of barite.

'There's a lot of people looking at these extreme habitats on Earth as models for what we might discover when we go to other planets,' Cordes told Seeker in May.

'The technology development in the deep sea is definitely going to be applied to the worlds beyond our own.'

HOW DID IT FORM?

During the Jurassic period, between 200 and 145.5 million years ago, a shallow sea existed on the site of the current Gulf of Mexico.

As plate tectonics continued its inexorable march onwards, this sea was eventually severed from the rest of the ocean.

In a warm world, this isolated sea began to evaporate, which ultimately left behind a mass of salt.

Researchers first found the formations in 2014 using a remotely-operated underwater robot called Hercules.

Eventually, the evaporated inland sea was flooded as it was once again connected to the world's oceans, but by this point, vast layers of salt several kilometers thick had already been covered by sediment.

However, as the weight of seawater squashed this salt down, some of it was forced back up onto the seafloor via a process called 'salt tectonics.'

This salt then interacted with the seawater, dissolved, and formed clouds of brine that settled on the seafloor.

One of the main purposes for revisiting this brine pool was to conduct a high-resolution mapping survey of the area.

'The top layer of the brine pool (surface down to 3 m depth) had very high salinity (80–110 psu) and a temperature of 7.8°C.

'Below this layer, we found dense, hydrocarbon-charged, fluidized mud at a temperature of 19°C,' the team said.

'The sampling line and CTD were lowered ~19 m into the pool but never reached a hard bottom—shedding new light on the nature of these 'bottomless' brine pools.'

One of the main purposes for revisiting this brine pool was to conduct a high-resolution mapping survey of the area.

Large dead isopods and crabs that had been preserved along the edge of the brine pool were spotted by the team.

The preliminary analyses confirmed that the brine pool was saturated with methane.

The team now hope to return to create 3D maps.

'Ongoing analysis of this experimental spectral data, together with high-resolution three-dimensional mapping, will provide a more detailed picture of the physical and biogeochemical processes at work in these extreme environments.

'This information helps us to estimate the amount and extent of microbial processes occurring in such environments and to better understand how these ecosystems are initially formed, how they change over time, and what controls the differences among them that we observed on these and other expeditions.'